Coastal and like defense unit



Jan. 4, 1944. w. A. PHILLIPS 2,333,354

COASTAL AND LIKE DEFENSE UNIT Filed Aug. 15, 1 941 2 Sheets-Sheet 1 5 12011 8 P ll g 12 9 4 27 l v J 7 6- Jan. 4, 1944. w. A.- PHILLIPS COASTALAND LIKE DEFENSE UNIT Filed Aug. 15, 1941 2 Sheets-Sheet 2 Patented Jan.4, 1944 I COASTAL AND LIKE DEFENSE UNIT William Arthur Phillips, London,England 7 Application August 15, 1941, Serial No. 407,075

In Great Britain August 23, 1940 2 Claims. (Cl. 114-4) This inventionrelates to coastal and like defense units having the form of floatingstructures or hulls which are capable of being grounded, anchored ormoored off the shore, or in estuaries or rivers for example, and whichare adapted to be equipped for defense against enemy attack or forauxiliary purposes. Such units may be of various kinds according to theservice they are required to perform. Thus for example a defense unitproper will comprise a floating hull having accommodation for a crew andprovided with suitable armament, but units constructed on the samegeneral principles and moreover of standard hull form may be adapted andequipped for use as store Vessels, Searchlight posts, wireless stations,anchorages for barrage balloons and other purposes. Large numbers of theunits may be grouped in appropriate surroundings at convenient distancesapart and may be disposed to afford the most effective co-operationbetween the units which may be adapted and equipped for differentpurposes. It will readily be understood, however, that the units have awide variety of uses particularly for war purposes but in many instancesisolated units may be effectively em- 'ployed. The hulls may also beadapted for use as floating residences, as hotels and for other peacefulpurposes.

For example, they may be employed as lightships or other aids tonavigation.

It is an object of the invention to provide a form of floating unit orhull for the purposes indicated which is particularly suited, in respectof th characteristics of seaworthiness and steadiness to the conditionsof service required.

Another object of the invention is to provide a defense unit of thecharacter described which will afford a high degree of steadiness andcontrolled action in a sea-way.

According to the invention, the unit comprises a buoyant structure orhull having a relatively great draft or depth as compared withconventional hull form, or as compared with the freeboard, and thevertical section being of interrupted or stepped form including an upperpart lying at the water plane joined to one or more lower parts ofsmaller diameter by a shouldered portion. Preferably the unit comprisestwo main parts, the upper part being of a relatively large area in plan(in relation to its depth) and the lower part being of smaller diameterwith a definite step or shoulder connecting the parts, which step may beeither fiat or inclined. The relative proportions of these parts arechosen to gi e a suitable initial stability combined with a' reasonablerolling period. It is Well understood that ordinarily a shallow draftvessel having a relatively large area at the water plane may haveinitial stability and a short rolling period, that is to say such avessel will be stiff and jerky in action in a sea-way. Conversely avessel having a deeper draft and a relatively small Water plane areawill generally have a long rolling period and easy movement in asea-way. Theform of unit described above partakes of both thecharacteristics referred to and thus provides the best conditions forthe service which the unit is required to perform, namely a reasonablysteady gun platform, a comparatively high initial stability, and asteady roll. It is preferred that the unit should be substantiallysymmetrical in plan although some deviation in one or other of thedifferent parts of the units may be made, e. g, such may be slightlyelongated, particularly the top section. In the preferred constructionthe curved sides and generally tapered conical section together with thespheroidal or dome-shaped (otherwise pearshaped) bottom are best adaptedto resist severe shocks by dispersing the forces which may be set up dueto explosions below the Water in the near vicinity. Having inherentresistance to collapse, the form takes full advantage of the propertiesof concrete, necessitating the minimum amount of steel reinforcement totake tensile strains. According to a further feature of the inventionthe step or shoulder which connects the parts of different diameter isin the form of an inverted truncated cone of large angle with apexdownwards and offers considerable resistance to rolling action. In somecases a circular keel may be formed below the bottom proper, offeringresistance to rolling and affording increased steadiness.

According to a further feature of the invention, the lower part of theunit, i. e., that having the smaller diameter, is also in the form of atruncated cone having a relatively small cone angle. This permits a moreequal distribution of pressure such as may be caused by a bomb explosionand affords greater freedom of movement in an upward direction. In orderto meet excessive strains in a vertical direction resulting from such anexplosion the floor or deck i preferably shaped and strengthened todistribute the strain as evenly as possible.

According to a further feature of the invention, the upper part of theunit is of substantially uniform cross section and is preferablypolygonal for greater ease in construction. The lower section may alsobe polygonal in plan, although cirdownwards.

cular sections in either or both parts may be adopted if desired.Moreover, the lower part may be substantially cylindrical or prismatic.

According to a further feature of the invention there may be providedstiffening webs extending between the upper and lower parts of thestructure external to the connecting shoulder. These webs will be ingeneral of triangular form and. they may be so constructed as to act asfins offering resistance to any tendency to rotation of the unit aboutits vertical axis and also resistance to rolling.

In the preferred mode of constructing the units, reinforced concrete isused, but other materials may be employed if desired. Provision may bemade for an outer covering of resilient and Waterproof material toreduce the effect of sudden shocks, as for example such as may be causedby a bomb exploding in the water nearby.

The interior of the structure will generally be provided with decks andsuitably equipped for the service required. Deck lights may be fitted.and these may be removable if desired.

Anv example of the preferred mode of carrying theuinvention into effectwill now be described with reference to the accompanying drawings,

:.in which:

Figure l is a vertical section through a floating defense unit accordingto .the invention;

Figure 2 is a plan View of the :unit; and

Figure. 3 is a partial sectional view showing the arrangement of thestrengthening 'webs.

.In carrying the invention into effect accord- "ing to one convenientmode, as-applied by way of example to a floating unit for accommodatinga crew of about six to twelve men, there is provided'a reinforcedconcrete hull, having an upper "part I which is substantiallycylindrical and of constant cross-section, and a lower part 2 in theform of an inverted truncated cone having a small angle withthe verticaland with the apex The depths of these two parts may be, for convenience,substantially equal and they are joined by a truncated conical shoulderor step portion 3 preferably lying at about the level of the lower deck.The diameter .of the upper portion may be, for example, about.twenty-two feet and the total depth of the unit about twenty 'feet.

Two decks are provided, an upper deck 4 with about three feet freeboard(i. e., about six feet to topof rail or solid bulwark) anda lower deck 5at about the level of the lower part of the connecting shoulder 3.reinforced concrete and are formed integral with the hull properrepresented by the portions I These decks are of and E. The arrangementmay be varied as desired, subject to providing sufficient freeboardaccording to the angle of inclination considered necessary. Each deckhas a large central aperture to enable the stores and equipment to beThis also provides support The lower deck is fitted up as quarters forthe ,crew and access thereto is obtained by way of fa hatch I 2 which isprovided with a hood lZa. A portable davit [.3 is providedforloweringstores and. aladder leads to the lower deck.

The lower deck 5 has a large central aperture which is covered by aremovable water-tight wooden floor IS. The space is subdivided bypartitions l6 and fitted with bunks ll.

Beneath the lower deck 5 is a stores compartment having a floor l8. Thebottom of the hull is provided with an upstanding annular wall 2|concentric with the hull which provides a support for, the floor I8 andalso for a water tank I9. Other :stores including ammunition may bedisposed in this lower compartment.

In order to strengthen the hull structure a number of stiffening webs orgussets may be pro- Lvided. Strengthening webs 22 ar provided under theupper deck 4 and are continued downwardly along the walls of the lowerdeck. Similar webs 23 are provided beneath the lower deck.

Additional stiffening webs 24 are provided in the angle formed by theconnecting shoulder, i. e., under the upper part of the hull structure.These webs extend in vertical .planes and are roughly trian ular inshape sothat .the main re.- inforcement may be conveniently carriedthrou h. They are suitably reinforced, the reinforcement connecting withthat of the mainhull structure. The cross-section of the .webs ispreferably slightly tapering to facilitate the removal of theshuttering. Any desired number of webs may be provided and they may alsoserve as steadying fins and for checking rotational movementof the unitabout the vertical axis. Webs 25 are also provided external to thebottomv 20 of the hull which slopestowards the centre.

The hull may be provided with fender members 26 and riding lights 21.The load water line is indicated at 28 and the light waterline at 28a.

It will be understood that the details of shape given abovemaybe widelyvaried without depart.- ing from the general principles previouslydefined. Thus while the hull structure is preferably circular orapproximately circular in plane, this may be modified by making certainor any of the parts/of an oval or other shape in plan. Thus for examplethe upper hull part may .be oval, or polygonal approximating to an .oval

form, and the remaining parts circular or prismatic,,.and variouscombinations may be adopted. In general, however, the plan of thstructure will be symmetrical or nearly so about a vertical axis and thedraft or depth will be relatively greater than the horizontaldimensio-nas compared with the conventional boat shape which is elongated in thehorizontal direction.

The invention may be applied with advantage to the defense unitsdescribed in the specification of British patent-application No. 10,822of 1 940 and may embody all the variations. suggested .therein. Whilethe preferred material is reinforced concrete it will beappreciated'that the advantages of the present invention may be obtainedwith-other materials, the choice of which will depend upon the suppliesavailable. Means may readily be provided for varying the metaprovidedfor this purpose and it is preferred that ,'.such chambers should besituated near the hot- .730

tom of the. hull.

. I. claim: v

1. .A floating structure ,of the type described having ,ahull; composedof an uppcrpart andfl lower part of re uced diamet Joined by a sOllldered portion, vertical uprights in the r-bottomef hatch provided inthe upper deck for establishing means for communication with the uppercompartment, the upper compartment being adapted to serve as livingquarters and the lower compartment as space for storing supplies.

2. A floating structure as claimed in claim 1, in which reinforcing ribsare provided on the inner surfaces of the side walls of the upper andlower parts of the hull and extend beneath the decks to the flangesabout the openings in the 10 adjacent decks.

WILLIAM ARTHUR PHILLIPS.

